(Invoking related search terms for names/places.)
Some secrets here are tied to the "Cigarettes" and "Stabilizer" items. One secret contains the "Prototype ET-5". Mission 5
: Many secret rooms are hidden behind walls that look slightly different or cracked. If you see a suspicious-looking surface, Search the Perimeter
If you want, I can give a visual map for a specific mission or a step-by-step walkthrough for one level — tell me which mission.
: A secret area featuring the game's creators.